Not to derail the topic at hand, but it was the Segway that proved the concept of dynamic stabilization, which in turn led to drones, bipedal robots, SpaceX’s reentry boosters, and much much more.
My point is that the Segway does seem like a silly device in retrospect, but it was actually profoundly impactful.
No, it was the cheap, good-enough inertial sensors that made that impact. Segway didn't invent them. Segway was beyond all hope when Weird Al made "White and Nerdy"
that’s exactly the the advancement that the segway represents, but while the sensors, actuators, and engineering were notable, it was mainly the advancement of computing power that enabled dynamic stabilization. before the segway, the computations couldn’t be done in real-time without (relatively) very expensive computers.
My point is that the Segway does seem like a silly device in retrospect, but it was actually profoundly impactful.